Grinding wheel reciprocating mechanism



Aug. 30, 1938;

H. SQINDGE GRINDING WHEEL REGIPROCATING MECHANISM Filed May 15, 19s? 2 Sheets-Sheet 1 Svwgm/fom HERBERT SINDQE Fig Aug. 30, 1938. H. s. INDGE I 2,128,675

I I GRINDING WHEEL BECIPROCATIITIG MECHANISM I Filed May 15, 1937- 2 Sh e ets-Sheet 2 HERBERT SIM/5E Patented mm, 1938 7 UNITED STATES PATENT oFFior.

ANISM Herbefl 8. Indie. Wcltboro, alllgnor to Norton Company, Worcester, Mass, :1. corpontlon of Massachusetts Application M3! 13, 1937, Seth! No. 142,344

,4 Claims.

The invention relates to grinding machines, and with regard-to its more specific features to a grinding wheel reciprocating mechanism.

One object oi the invention is to provide a 5 simple and effective mechanism for reciprocating be in cart obvious or in port pointed out hereinafter.

The invention occordingly consists in the leoturcs of construction, combinations of elements and arrangements of ports, as will be exemplified in the structure to behereiooiter described, and the scope oi the application of which will be indi coted in izhe following claims.

In the accompanying drawings showing one oi various possible embodiments oi the mechouicol lectures or this invention,

Figure l is s plan view of o grinding moohine constructed luhccordonce with the invention;

Figure 2 is s front elevation oi o wheel slide incorporating the invention;

Figure 3 is enelevssioh oi the electric actuating and controlling mechsxiis v Figure 4- is o sectional view, on an enlarged scale, of the grinding wheel, its mounting and solenoid actuating device; and

Figure s is a wiring diagram;

Figure s iso. wiring diagram showing a modifi cation of the invention.

Referring first to Figure 1', the grinding ma chine may include a. boss is upon the upper surface of which are formed ways ll, l2 supporting the ususl rcciprocctory carriage is having as G headstock as and o lsilstoch is adiustelbly mounted thereon. Incorporated in the headstock ha a motor Ell which, by moons of reduction georing in the casing ll, drives a, face plate It. The head center id and the call center 21?, the former on the headstock M and the latter on the tailstcclr. l5, support a work piece 2! to be ground. The worir piece is gripped by e'dog 22 connected to the face plate id. The machine incorporates any usual or desired deviceior moving the carriage l8 or adjusting its position, tor example a rack and pinion gear, not shown, operated by a hand wheel 25.

Mounbed on o. rearward extension 26' of the base I0 is a, cross slide 21. The cross slide can be ad- 55 lusted in a direction normal to the wcys H, II by means of e feed screw 28 controlling a. nut 29 secured to the carriage 21, the feed screw 28 being operated by means 0! a. hand wheel so. Mounted on the cross slide 31. is a motor 3! which drives a pulley 32 which is connected to a, pulley 33 by means of a plurality of belts 34. The pulley 83 is mounted on s spindle 86, upon the opposite end of which is mounted a grinding wheel 4d.

Rhiemirig now to Figures 2 and 4, the spindle 36 between the grinding wheel on and the pulley 33 constitutes a straight cylindrical shell which is journo-led in plain bearings M in cross slide castlog 2?, as shown in Figure 2. Consequently, by reason of the loci; that the bolts M ore flexible (being orciershly V-shobed driving belts), the i5 spindle 36 my move endwlse for is limited disiaonce Bolted to the left-hand side of the wheel head @i is on scale bracket $5. This bracket so has o supporting portion cs for o solenoid ll. Similerly, to the right-hsnd side of the cross slide 2'3 is boiled on angle broclrei: to having as supporting oorliou so for o solenoid 59. As shown in Figures 3 sud Ea, provide on electric motor so upon the umisitui'e shell, of which I mount a commutator."

, ihsulsclno' rink; 56 bovine? s metallic commutator coouecler Elli dismeigrlccllv theresci'oss. A pair cl concoct brushes 5E sud 5d are mounted on on insulating block Bil A pair of contact brushes ill and so are mounted upon an insulating block so. The disfcehce between the brushes 5d and 59 is the some as that between the brushes 8! and 62 and is slightly less than the length of the commutator conductor bl. The brushes 58 and El as well as the brushes 6i and 62 surround the commutator block and the brushes 58 and W are each of them perpendicular to each of the brushes 6i and 82. Consequently, as the commutator 5b is revolved, the brushes 58 and 59 will be connected, and them the brushes 6i and 62 will be counseled. With the ports proportioned as shown in Figure 3, the connection between each pair of brushes is maintained for a substantial annular displacemerit of the commutator member 51, for example 25 thereof at each contact.

Rcicrring-now to Figure 5, I provide main line conductors 5B and 66. The motor 55 is connected by o conductor 61 and switch 68 to the line 65 on one side and by a. conductor 68 and rheostat Hi to 50 the line 86 on the other side. By means of the rheostat Ill thespeed of the motor 55 may be readily varied. The brush 5B is connected to the line 88 by means of a conductor ll and switch 12. The brush i9 is connected by means of a con- 55 Ill ductor 1.3 to one terminal of the solenoid H. The other terminal of the solenoid H is connected by means of a conductor M to the line till. iilmliarly, the brush 8! is connected by a conductor it and switch 18 to the line 88, the brush this connected to one terminal of the solenoid lit by a conductor ll, and the other terminal oi th solenoid. bi l is connected by a terminal it to th By means of the foregoing appai solenoid 41 and B0 is energised twice ring each revolution oi the commutat .r and the Him"- gizations arc alternate. itemization oi ouch solenoid is ioliowed by a anti deenergizatiun thereof and i energized at a time.

Referring now particularly to Figure 4, the spindle It has a reduced portion iii] upon "whim. the grinding wheel ll) is mou ed. .il shoulder II on the spindle 38 provides backing'ilor a plate I! which is bolted to ii. p. to 33 by bolts 84 extending through the grinding wheel Mi. The reduced portion lii is threaded and is in threaried engagement with the plate M. A nut llii mounts the wheel upon the spindle and secures it thereto. The threaded portion In of the spindie 38 extends beyond the nut 35 and a brass sleeve 81 which is internally threaded is mounted thereon. Secured to the other end of the brass sleeve 81 is a core N which may take the form of a cylinder of soitiron having a reduced threaded projecting portion 85 which is in threaded engagement with the inside of the sleeve 81.

Referring now to the right-hand side 01' Figure 4. at the right-hand end of the spindle 36 is a reduced portion 90 upon which is mounted the pulley 33 that is keyed thereto. The righthand extremity of the reduced portion 90 is threaded, and screwed thereon is a brass sleeve 81 upon the far end of which is mounted a soft iron core 98 which may be identical with the core 88, having also a threaded portion 99 for connection to the sleeve 81.

As indicated in Figure 4, when one core 88 is in the center of a solenoid, the other core is slightly withdrawn therefrom. As iirst one and then the other solenoid is energized, first one and then the other core 88 and 88 is drawn into the corresponding solenoid 41 and 50. This reciprocates the spindle I8 and, therefore, the

but at high speeds the spindle does not travel iii.

It is gniy J wheel. lliili'iiii till be consli; era v order oi a small from 1.. at higher cycles oi. The reciprocation itself may be it tlon as it is feasible to vibrate the W different speeds of vibration inciuii a the order of ill) cycles o. second, taster slower.

Referring now to Figure 6, "I have shown a modification of the intention ich in some respects is simpler than the ernigiotiiment previously described. In this modification of the invention, however, the rate oi" vibration is 60 cycles a second in those portions of the United States where alternating current oi 'iil cycles is available, and 25 cycles a second in those portions of the United States where 25 cycle current is available. In Europe and places where 50 cycle current is used, the rate of vibration would be 50 cycles. In other words, according to this embodiment of the invention in. Figure ii, the rate of vibration of the wheel is the same as that of the frequency oi "the current available.

In the modification of Figure 6, the mecliicnical parts and features are or may be substantially as already described. Solenoids ii and Eli are provided. I further provide main conductors I00 and ill! energized with single phase alter noting current, for example volts at till cycles. I connect one terminal of the solenoid M to the line Hil by means of a conductor N32. I connect one terminal of the solenoid Bill to the line MI by means oi a conductor I03. I connect "the terminal oi? solenoid IT to the line M0 by means of a conductor ill! in which is interposed a rectifler I05. I connect the other terminal 01 the solenoid 50 to the line Hill by means of a conductor Hit in which is interposed a rectiiier I01.

It will be apparent that since current can flow only one way through each circuit including the solenoids l! and 50 respectively, each solenoid I1 and Ill will be alternately energized and deenergized with alternations of the current. Furthermore, as the rectitlers I O5 and llil are oppositely oriented, the solenoids 41 and 50 will be alternately energized. This will cause the wheel 40 to vibrate with the frequency of the current. -I have found that an excellent finish is achieved with a grinding wheel vibrating at a vfrequency oi the order indicated.

So far as certain features of the invention are concerned an electromagnet and an armature might be substituted for a solenoid and a core. but the solenoid and core has the advantage that a more constant pull over a greater amplitude is achieved. i

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinhefore set forth or shown in the accom panyiug drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:-

1. In apparatus of the class described, an abra= sive wheel, a spindle therefor, a pair of electromagnetic devices one of which will pull the spindle in one direction and the other of which will pull the spindle in the other direction, a source of alternating current, lines connecting each electromagnetic device to the source, and rectiflers interposed in the lines whereby to vibrate the abra sive wheel with the frequency of the alternating current.

2. In apparatus of the class described, an abra-- sive wheel, a spindle therefor, electromagnetic tator whereby to vary the frequency of vibration or the abrasive wheel.

3. In apparatus 01 the class described, an abraaive wheel, a spindle therefor, a pair of solenoids, a pair of cores, two of said last mentioned four parts being attached to the spindle and rotating with it, the other two of the said last mentioned four parts being relatively stationary, a commutater to control the energiaation of the solenoids, and means to vary the speed of rotation of the eommutator whereby to vary the frequency of vibration of the abrasive wheel.

4. In apparatus of the class described, an abrasive wheel, a spindle therefor, a pair of solenoids, a pair of cores, two of said last mentioned four parts being attached to the spindle and rotating with it, and the other two of the said last mentioned four parts being relatively stationary, and alternating current means and rectifiers connected to the solenoids alternately to energize them whereby to vibrate the abrasive wheel with the frequency of the alternating current.

HERBERT S. INDGE. 

